/// Execute a block node or function "process".
/// \p user_ios contains the list of user-specified ios, used so we can avoid stomping on them with
/// our pipes. \return true on success, false on error.
static bool exec_block_or_func_process(parser_t &parser, job_t *j, process_t *p,
const io_chain_t &user_ios, io_chain_t io_chain) {
assert((p->type == INTERNAL_FUNCTION || p->type == INTERNAL_BLOCK_NODE) &&
"Unexpected process type");
// Create an output buffer if we're piping to another process.
shared_ptr<io_buffer_t> block_output_io_buffer{};
if (!p->is_last_in_job) {
// Be careful to handle failure, e.g. too many open fds.
block_output_io_buffer = io_buffer_t::create(STDOUT_FILENO, user_ios);
if (!block_output_io_buffer) {
job_mark_process_as_failed(j, p);
return false;
} else {
// This looks sketchy, because we're adding this io buffer locally - they
// aren't in the process or job redirection list. Therefore select_try won't
// be able to read them. However we call block_output_io_buffer->read()
// below, which reads until EOF. So there's no need to select on this.
io_chain.push_back(block_output_io_buffer);
}
}
if (p->type == INTERNAL_FUNCTION) {
const wcstring func_name = p->argv0();
auto props = function_get_properties(func_name);
if (!props) {
debug(0, _(L"Unknown function '%ls'"), p->argv0());
return false;
}
const std::map<wcstring, env_var_t> inherit_vars = function_get_inherit_vars(func_name);
function_block_t *fb =
parser.push_block<function_block_t>(p, func_name, props->shadow_scope);
function_prepare_environment(func_name, p->get_argv() + 1, inherit_vars);
parser.forbid_function(func_name);
internal_exec_helper(parser, props->parsed_source, props->body_node, io_chain);
parser.allow_function();
parser.pop_block(fb);
} else {
assert(p->type == INTERNAL_BLOCK_NODE);
assert(p->block_node_source && p->internal_block_node && "Process is missing node info");
internal_exec_helper(parser, p->block_node_source, p->internal_block_node, io_chain);
}
int status = proc_get_last_status();
// Handle output from a block or function. This usually means do nothing, but in the
// case of pipes, we have to buffer such io, since otherwise the internal pipe
// buffer might overflow.
if (!block_output_io_buffer.get()) {
// No buffer, so we exit directly. This means we have to manually set the exit
// status.
if (p->is_last_in_job) {
proc_set_last_status(j->get_flag(job_flag_t::NEGATE) ? (!status) : status);
}
p->completed = 1;
return true;
}
// Here we must have a non-NULL block_output_io_buffer.
assert(block_output_io_buffer.get() != NULL);
io_chain.remove(block_output_io_buffer);
block_output_io_buffer->read();
const std::string buffer_contents = block_output_io_buffer->buffer().newline_serialized();
const char *buffer = buffer_contents.data();
size_t count = buffer_contents.size();
if (count > 0) {
// We don't have to drain threads here because our child process is simple.
const char *fork_reason =
p->type == INTERNAL_BLOCK_NODE ? "internal block io" : "internal function io";
if (!fork_child_for_process(j, p, io_chain, false, fork_reason, [&] {
exec_write_and_exit(block_output_io_buffer->fd, buffer, count, status);
})) {
return false;
}
} else {
if (p->is_last_in_job) {
proc_set_last_status(j->get_flag(job_flag_t::NEGATE) ? (!status) : status);
}
p->completed = 1;
}
return true;
}
/// Return a definition of the specified function. Used by the functions builtin.
static wcstring functions_def(const wcstring &name) {
CHECK(!name.empty(), L""); //!OCLINT(multiple unary operator)
wcstring out;
wcstring desc, def;
function_get_desc(name, desc);
function_get_definition(name, def);
std::vector<std::shared_ptr<event_handler_t>> ev = event_get_function_handlers(name);
out.append(L"function ");
// Typically we prefer to specify the function name first, e.g. "function foo --description bar"
// But If the function name starts with a -, we'll need to output it after all the options.
bool defer_function_name = (name.at(0) == L'-');
if (!defer_function_name) {
out.append(escape_string(name, true));
}
if (!desc.empty()) {
wcstring esc_desc = escape_string(desc, true);
out.append(L" --description ");
out.append(esc_desc);
}
auto props = function_get_properties(name);
assert(props && "Should have function properties");
if (!props->shadow_scope) {
out.append(L" --no-scope-shadowing");
}
for (const auto &next : ev) {
const event_description_t &d = next->desc;
switch (d.type) {
case event_type_t::signal: {
append_format(out, L" --on-signal %ls", sig2wcs(d.param1.signal));
break;
}
case event_type_t::variable: {
append_format(out, L" --on-variable %ls", d.str_param1.c_str());
break;
}
case event_type_t::exit: {
if (d.param1.pid > 0)
append_format(out, L" --on-process-exit %d", d.param1.pid);
else
append_format(out, L" --on-job-exit %d", -d.param1.pid);
break;
}
case event_type_t::job_exit: {
const job_t *j = job_t::from_job_id(d.param1.job_id);
if (j) append_format(out, L" --on-job-exit %d", j->pgid);
break;
}
case event_type_t::generic: {
append_format(out, L" --on-event %ls", d.str_param1.c_str());
break;
}
case event_type_t::any:
default: {
DIE("unexpected next->type");
break;
}
}
}
const wcstring_list_t &named = props->named_arguments;
if (!named.empty()) {
append_format(out, L" --argument");
for (const auto &name : named) {
append_format(out, L" %ls", name.c_str());
}
}
// Output the function name if we deferred it.
if (defer_function_name) {
out.append(L" -- ");
out.append(escape_string(name, true));
}
// Output any inherited variables as `set -l` lines.
std::map<wcstring, env_var_t> inherit_vars = function_get_inherit_vars(name);
for (const auto &kv : inherit_vars) {
wcstring_list_t lst;
kv.second.to_list(lst);
// This forced tab is crummy, but we don't know what indentation style the function uses.
append_format(out, L"\n\tset -l %ls", kv.first.c_str());
for (const auto &arg : lst) {
wcstring earg = escape_string(arg, ESCAPE_ALL);
out.push_back(L' ');
out.append(earg);
}
}
// This forced tab is sort of crummy - not all functions start with a tab.
append_format(out, L"\n\t%ls", def.c_str());
// Append a newline before the 'end', unless there already is one there.
if (!string_suffixes_string(L"\n", def)) {
out.push_back(L'\n');
}
out.append(L"end\n");
return out;
}
